In daily life, people will come into contact with a variety of electrical devices, for example, household appliances used in the family such as air conditioner, television set, refrigerator, washing machine, tablet computer, and the like; displays used in the subway or public transport system; as well as various players, mobile phones and the like that can be carried on the person. During use of these electrical devices, they often fail for some reason, even failing during an early stage of use. For example, a black screen may occur in displays and mobile phones. Refrigerators and washing machines may not start up normally; and so on. After occurrence of these failure phenomena, it is usually required to examine and test the failed electrical device in order to obtain the cause of failure, or even required to make experiments to find the cause of failure, so as to repair the failed electrical device. For example, it may be required to dissect the hardware of an electrical device or simulate a failure phenomenon. Apparently, this solution to determine the cause of failure may be overly dependent on experience, and the process thereof may also be relatively cumbersome, resulting in low efficiency.